1. Field of the Invention
The invention relates to can openers with manual turning knobs.
2. Description of Prior Art
All types of food are stored in cans sealed with metallic lids. The outside surface of the lid is exposed to all types of contaminants, such as dust, or dirt from packaging, storage and handling. In opening cans, it is important for obvious sanitation reasons that the outer surface of the lid does not contact any portion of the food in the can.
It is equally important for safety reasons that can openers allow the user to easily sever a lid from a can and to remove the severed lid.
In the prior art, can openers with manual turning knobs focus primarily on severing the lids of cans. Even so, many of the manual turning knobs developed are spherical, round, bar-shaped or rectangular in shape. Such a design is difficult for users who have arthritis, since turning a rectangular knob requires greater flex or rotation of the wrist, thus causing stress and consequent pain to the user with an arthritic wrist.
Severing the lid from the can, however, is only half of the process of opening a can. Safely removing a severed lid is equally important. To avoid having the external or top surface of the lid contact the food contents, a user will often avoid completely severing the lid. Leaving a small portion of the boundary of the lid attached to the can keeps the lid from being immersed in the food contents. However, the user must then use his or her hands or a knife to twist and turn the lid such that it will completely detach from the can. This dangerous use of the hands often leads to cuts from the sharp edge of the lid as the user attempts to somehow detach the lid.
Alternatively, a user may choose to completely sever the lid using the prior art can openers. However, once the lid is completely severed, the lid will drop and immerse into the food contents. This poses serious sanitation problems as the contaminants from the outer surface of the lid become absorbed by the food contents.
Therefore, what is needed is a can opener that makes it easier for the user to turn, prevents the upper surface of the lid from touching the food contents, and provides a safe way for removing the lid. What is also needed is a method of opening a can that will accomplish the above objectives.